Description

If integrity check values or "checksums" are not validated before messages are parsed and used, there is no way of determining if data has been corrupted in transmission.

Consequences

Authentication: Integrity checks usually use a secret key that helps authenticate the data origin. Skipping integrity checking generally opens up the possibility that new data from an invalid source can be injected.

Integrity: Data that is parsed and used may be corrupted.

Non-repudiation: Without a checksum check, it is impossible to determine if any changes have been made to the data after it was sent.

Exposure period

Implementation: Checksums must be properly checked and validated in the implementation of message receiving.

Platform

Languages: All

Operating platforms: All

Required resources

Any

Severity

High

Likelihood of exploit

Medium

The failure to validate checksums before use results in an unnecessary risk that can easily be mitigated with very few lines of code. Since the protocol specification describes the algorithm used for calculating the checksum, it is a simple matter of implementing the calculation and verifying that the calculated checksum and the received checksum match.

If this small amount of effort is skipped, the consequences may be far greater.